Hermann ulsmann



NITE STATES PATENT Trice HERMANN ULSMANN, OF KONIGSHUTTE, PRUSSIA, GERMANY, ASSIGNOR TO EDWARD COOPER, OF NEW YORK, N. Y.

MANUFACTURE OF FURNACE-LININGS.

SPECIFICATION forming part of Letters Patent No. 273,917, dated March 18,1888,

(No specimens.)

To all whom it may concern:

Be it known that I, HERMANN ULSMANN, a citizen of the German Empire, residing at Konigshiitte, in the Kingdom of Prussia and German Empire, have invented new and useful Improvements in the h'lanui'acture of Furnace-Linings, FireBricks, 8230., of which the following is a specification.

The object of this invention is to increase the cohesion or strength of purely basic fireproof materials manufactured from natural or artificial caustic alkaline earths, or their carbonates, such as lime or magnesia, either alone or in combination.

Heretotore the process of dead-burning and slaggmg of the alkaline earths was effected by long or repeated burning at the highest temperatures, or by mixing with watery solutions of caustic alkaliesorcarbonates orchloridesthereof, or of the alkaline earths. Instead of these watery soluti0ns,I now use the ferrous alkaline earths, such as exist in nature-for instance, magnesium ferric carbonate-or such as can be produced artificially, or I add to the alkaline earths iron in a metallic or oxidized condition, or as carbonate chloride, or in another suitable combination in form of small fragments or powder. On exposing the mixture to a high temperature the alkaline earths combine very readily with the corresponding oxides, and while they lose all the carbonic acid which they may contain, they are converted thereby, with considerable shrinkage, into a very hard splintery, granular, brittle mass, which, like the natural magnesium ferric carbonates and like the roasted spathic iron ore, crumbles into small pieces. The brittleness of this slagged mass and its tendency to fall into pieces facilitate its reduction for the subsequent operalions, in which it is important that only a portion should be ground fine, while another portion, dependent upon the purpose to which the mass is to be applied, should be left in granules of from 0.039 to 0.19 inch in size, or even larger, and with the sharpest possible corners or edges, in order to produce therefrom, with the admixture of suitable binding materials, coarse-grained bricks and other articles of a similar grain in the fracture as those prepared from burned and pulverized lire-clay, which re- 5 3 sist all the varying influences of heat and cold.

The binding material which I employ consists of an intimate mixture of linely-pulver ized anhydrous alkaline carbonates-such as soda or potash, either alone orin combinationwith tar free from water, or other hydrocarbon of aviscous nature in the cold or warm state. By the addition of this mixture to the above-described siagged and reduced alkaline earths a plastic mass is obtained which, when warmed, can be readily pressed in the form of bricks, pipes, or vessels, and which can be applied directlv as lining for metallurgical apparatuses. lies or of alkaline compounds which contain Water of hydration, or which have a tendency to take up water from the air, have in this case a detrimental action, because the strength of the bricks or of the stamped lining is liable to be impaired thereby at the subsequent burning. By the methods heretofore employed for the manufacture of basic lire-proof materials, in which watery solutions of caustic alkali or alkaline cal bonates, either alone or combined, with the subsequent admixture of tar are used, no satisfactory results can be obtained as regards the strength and durability of the products, because the tar alone affords a binding material of but little strength under the influence of heat, and because the water contained in the alkaline solutions forms hydrates with the alkaline earths and alkalies, the decomposition of which, under the influence of heat, when being burned, renders the fire-proof material loose. It is also not sufiicient to add to the fundamental mass of alkaline earths or their carbonates only one per cent. or a small percentage of alkaline carbonates or caustic alkalies as binding material; but it requires an ample addition of alkaline carbonates for this purpose. I have found that at least five per cent. of the alkaline carbonates must be added to ninety-five percent. ofthe dead-burned slagged fundamental mass in order to obtain a good result. The quantity of tar employed should not be greater than actually necessary for uniting the warmed mass under pressing or stamping to a solid mass. 1t may be one- The admixture of caustic alkatenth of the weight of the fundamental mass ofdead-burned alkalineearths; but the proportion depends essentially upon the degree of toughness or fluidity of the tar.

For the purpose of burning and slagging the alkaline earths, reverberatory or shaft furnaces canobe used; but care must be taken that no ashy constituents containing silicic acid are added, and also that the highest possible temperature be employed, while quenching with water must be avoided.

If the bricks, pipes, vessels, or other articles produced in the manner above described.

a basic floor when used for lime bricks.

Fragments of burned material, or of used linings of the above nature, can be ground and re-formed by the addition of tar and reburning. 1f the dead-burning and slagging of the alkaline earths is effected with addition of chlorides of the alkaline earths or the alkalies with or Withoutthe admixture of fluor-spar, it is advisable to introduce steam at the deadburning in order to drive off the chlorine. The dead-burning can be accelerated bv the addition of small quantities of caustic alkalies or their carbonates.

I am aware that refractory brick has been produced by a mixture of newly-burned lime with tar. In this manufacture magnesia limestone is used, containing. before calcination, from five toseven per cent. of silica and from three to four per cent. of alumina and iron ox= ide. This material, after burning, is mixed with tar, or tar and creosote, in a mortar-mill preparatory to its being pressed in molds.

By my invention I avoid the presence of silica, and fora binding material tarorsoinesimilar hydrocarbon mingled with alkaline carbonates t'ree from water is employed.

'What I claim as new, and desiic to secure by Letters Patent, is-.-

1. The compound for basic furnace-linings, fire-brick, and other articles, consisting of a fundamental massprepared by dead-burning and slagging alkaline earths-such as lime or magnesia-in the presence of iron or oxide or other combination thereof free from silicic acid, and of a mixture prepared ot' hydrocarbons free from water and of a viscous nature, with alkaline carbonates free from water.

2. The within-described process for manufacturing basic fire-proof materials by first dead-burning and slagging the alkaline earths with admixture of iron or other combination thereof free from silicic acid, then comminuting the fundamental mass thus obtained, then adding thereto a mixmre of tar or other similar hydrocarbon with alkaline carbonates free from Water, and, finally, molding, pressing, or stamping the compound into the required forms.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

H ERMANN ULSMANN.

Witnesses EDUARD FEUERsTEIN, WICHHELM DiIRRoEsT. 

